Roof-covering element

ABSTRACT

The present invention relates to A roof-covering element ( 10 ), with an upper surface ( 11 ) and a lower surface ( 12 ), whereby for roof covering a plurality of elements ( 10 ) is juxtaposed in a particular way such that neighbouring elements ( 10 ) are interconnected by means of an interlocking arrangement ( 13, 14, 15 ), and whereby the roof-covering element ( 10 ) comprises means for exchanging heat with the environment, where at least one of the surfaces ( 11, 12 ) of the element ( 10 ) is at least partially made of a metal alloy. The particular roof-covering element ( 10 ) can in particular be made of an alloy comprising any combination of copper (Cu), zinc (Zn), manganese (Mn) and iron (Fe), i.e. the alloy CuZn 40 Mn 2 Fe 1 . The roof-covering element ( 10 ) according to the present invention can also comprise a cavity ( 16 ), provided inside the element ( 10 ), in which a fluid is circulable for heat exchange with the environment. The roof-covering elements ( 10 ) according to the present invention can be interconnected by means of a tubing system ( 25 ) for the circulation of the fluid between different elements ( 10 ).

TECHNICAL FIELD

The present invention relates to a roof-covering element, having anupper surface, a lower surface and an interlocking arrangement forinterconnecting neighbouring elements, whereby a plurality of elementsis juxtaposed in a particular way for roof covering. The presentinventions relates in particular to such a roof-covering element whichcomprises means for heat exchange with the environment.

BACKGROUND ART

The roof, i.e. the top covering of a building, can essentially be foundon each and every building in the world. On one hand, the purpose of aroof is to shed rain water off the building and to prevent it fromaccumulating on top of the building. On the other hand, roofs have amore and more important decorative function. To realise theseobjectives, roofs can be built with different forms and shapes and usingmany different materials. With respect to the form, roofs can be highlypitched (sloped) or low sloped in form. While pitched roofs are ingeneral found on industrial or commercial type structures, low slopedroofs are the primary design found on residential homes. As roofs arefully faced toward the sky, they must resist to all weather conditions.In particular, they have to be watertight, secure, durable, attractiveand elastic enough to withstand important temperature shifts withoutcracking. Subsequently, roof-building techniques and roofing materialshave been refined continuously for centuries to bear roofs ofconsiderable strength and durability.

Over the millennia, people have surfaced their homes with just aboutanything that would hold the weather out, from animal skins to treebark. Today, there are many roofing options with respect to thematerial, colour, shapes etc. The use of different roofing materialsdepend largely on particular weather conditions, but also and aestheticcriteria. Traditional roof coverings—slate and wood shakes—have remainedvirtually unchanged for centuries. On the other hand, new materials suchas asphalt/fibreglass composites, lightweight concrete and metal tilesare products of the technological revolution. Each of these materialshas slightly different durability, appearance, cost and ease ofapplication. Furthermore, contemporary roofs are complex systems, madeup of a variety of components that work together.

In the last decades, the so called solar roofing systems haveincreasingly been used for roof covering. These systems are designed insuch a way to be able to generate electricity and/or to produce hotwater or hot air, in addition to act as a roof covering. Typically,these systems make use of the so called solar cells. A solar (orphotovoltaic) cell is a piece of equipment that is capable of convertingthe solar energy into another kind of energy. An assembly of solar cellsis generally referred to as a solar panel. Historically, solar cells andpanels have been used in cases where electrical power from the grid wereunavailable. Recently, solar cells have though been more and more usedas a source of “clean” or alternative energy, in contrast to “dirty”power from nuclear power plants.

Solar systems can be built-in in roofs in many different ways. On theone hand, solar cells can be directly integrated in the covering ofpitched roofs. These systems are usually referred to as solar shingles.Essentially, solar shingles are solar cells shaped like a conventional(slate or ceramic) shingle.

They are designed to fit nicely onto many different types roofs and tobe compatible with regular shingles. Nevertheless, solar systems canalso be mounted on an existing roof, e.g. solar panel on a tile roof, orintegrated in a flat roof.

However, all known solar roofing systems present a number of hugedisadvantages compared with regular roofs. To start with, all solarpanels have a deep, dark, purplish-blue colour, such that roofs coveredwith the solar roofing systems look completely different than otherroofs. Moreover, the installation of solar roofing systems is prohibitedin different circumstances, i.e. in particularly old buildings orbuildings of a particular historical relevance. Moreover, the majorityof solar cells has an important dazzling effect, which can be a sourcefor important inconvenience in the entire neighbourhood. An additionalproblem of conventional solar systems arise in connection with theintegration of these solar systems in existing roofs. As solar roofingsystems become increasingly popular, more and more house proprietorswants to replace existing roofs by solar roofs. Nevertheless, solarpanels represent an additional weight for the underlying roofconstructions, such that installing solar panels is often possible onlyafter a thorough renovation of the whole roof structure. Similarproblems arise with solar shingles, where the replacement ofconventional shingles usually requires a new static calculations and animportant modification of the roof support.

On the other hand, the so called geothermal exchange heat pumps orground source heat pumps (GSHP) become also a more and more popularsource of energy for heating buildings. These ground sorce heat pumpsuse the Earth as either a heat source, when operating in heating mode,or a heat sink when operating in cooling mode. Geothermal heat pumpshave an external loop containing water or a water/antifreeze mixture,and a much smaller internal loop containing a refrigerant. Both loopspass through the heat exchanger. There are also the so called air sourceheat pumps (ASHP), which use the same principle but extract the heatfrom the air, rather than the ground. Thus, the installation of thesepumps is simpler and cheaper.

However, these air source heat pumps present the drawback that, in thecooling mode, the evacuation of the superfluous heat is sometimesdifficult. Some systems using air source heat pumps employ thereforeadditional cooling devices, such as ventilators, in order to draw offthe heat. These ventilators are an additional ennoyance for theneigbours and contribute also to the high costs of these systems.

DISCLOSURE OF INVENTION

It is thus an objective of this invention to propose a new and improvedroof-covering element that does not present the above-mentionedinconveniences and disadvantages of the prior art.

According to the present invention, these and other objectives areachieved in particular through the features of the independent claims.In addition, further advantageous embodiments follow from the dependentclaims and the description.

In particular, this objective is achieved through the invention in that,in a roof-covering element, having an upper surface and a lower surface,whereby for roof covering a plurality of elements is juxtaposed in aparticular way such that neighbouring elements are interconnected bymeans of an interlocking arrangement, and whereby the roof-coveringelement comprises means for exchanging heat with the environment, atleast one of the surfaces of the element is at least partially made of ametal alloy. The advantage of such a device is, among other things, thatthe roof-covering element can be produced of a natural material. A metalalloy is a particularly suitable material for this purpose, as the kindof alloy and the mixing ratio of the different compounds can be chosento satisfy all different requirements of the particular roof. Inparticular, an iron or aluminium alloy can be used in connexion withmodern buildings, where the silvery shine of these materials can beparticularly advantageous. In addition, a particular metal alloy to beused can be chosen in function of its thermal or mechanicalcharacteristics for an optimal protection against atmospheric conditionsand environmental influences.

In an embodiment variant, the metal alloy comprises any combination ofcopper (Cu), zinc (Zn), manganese (Mn) and iron (Fe). This embodimentvariant has the particular advantage, among other things, that the metalalloy comprising a combination of these components has a particularlyadvantageous proprieties with respect to the thermal, mechanical andchemical aspect. Thus, a roof-covering device made of this kind of metalalloy is particularly suitable for the realisation of the presentinvention.

In another embodiment variant, the metal alloy comprises the alloyCuZn₄₀Mn₂Fe₁. The alloy CuZn₄₀Mn₂Fe₁ has the particular mechanicalcharacteristics, that make it very suitable for the present invention.In particular, this alloy, known also under the trademark DORNA-A® has aparticular surface colour that is not substantially different from thecolour of the conventional tiles or other similar roof-coveringelements. Thus, a roof-covering element according to this embodiment ofthe present invention has the advantage of being very easilyinterchangeable with the conventional roof-covering elements.

In another embodiment, a cavity is provided inside the element, betweenthe upper surface and the lower surface of the element, whereby a fluidis circulable in the cavity for heat exchange with the environment. Theadvantage of this embodiment is, inter alia, that a fluid can be broughtto circulation inside the roof-covering device for heat exchange withthe environment. The roof-covering element offers a good platform forheat exchange between the fluid and the outside air, through naturalconvection. Moreover, the sun light can heat the fluid inside the cavityof the roof-covering element such that the heat exchange can work inboth directions (i.e. cooling or heating of the fluid). In this way, thebuilding with the roof made of roof-covering elements according to thisembodiment of the present invention can be heated or cooled, dependingon the needs. Moreover, this particular embodiment of the presentinvention allow a good collaboration with air source heat pump systems,where the superfluous heat can easily be dissipated in the environment.

In a further embodiment, at least one nipple with an opening is providedin at least one surface of the element, whereby the opening of thenipple is connected with the cavity. This embodiment has the advantage,among other thins, that the fluid can easily be filled in the cavity, orextracted from the cavity of the roof-covering element. The nipple hasin addition the advantage that a tube or another similar device can beeasily attached to it and thus to the roof-covering element, forcirculating the fluid.

In a further embodiment, the cavity comprises a channelling system.

The advantage of this embodiment is, among other things, that theinternal surface of the cavity of the roof-covering element can beincreased, such that the heat exchange with the environment can befacilitated. Using an appropriate channelling system, the internalsurface can be significantly increased, such that a much better heatexchange rate can be achieved in comparison with similar other deviceswithout such a channelling system.

In another embodiment of the present invention, the upper surface and/orthe lower surface of the element comprises a fin structure. The finstructure can in particular be formed similar to the structure of aradiator or a similar device. The advantage of this embodiment is, amongother things, that the particular fin structure of the surface of theroof-covering element allows to render possible a very efficient heatexchange with the environment. As at least one of the surfaces of theroof-covering element in a preferred embodiment is at least partiallymade of a metal alloy, the heat exchange with the environment can beaccelerated and expedited using the special fin structure with a largersurface.

In another embodiment, the fluid is water and/or an aqueous solution.Water is very suitable for heat exchange thanks to its advantageousthermal characteristic. In the same way, aqueous solutions, inparticular solutions with an antifreeze matter help to achieve an evenmore important effect.

At this point, it should be stated that, besides the roof-coveringelement according to the particular embodiments of the invention, thepresent invention also relates to an assembly of roof covering elements,a heat exchange system in a building or similar structures, a method ofmanufacture of a roof-covering element and a method for roof coveringusing the roof-covering element according to the present invention.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be explained in more detail, by way ofexample, with reference to the drawings in which:

FIG. 1 is a perspective representation of a conventional roof-coveringelement;

FIG. 2 is a perspective representation of an assembly of conventionalroof-covering elements of FIG. 1, which are juxtaposed in rows andcolumns and interconnected by means of an interlocking arrangement forcovering one part of the roof;

FIGS. 3 a and 3 b are sectional representations of two embodiments ofthe roof-covering element according to the present invention;

FIG. 4 are perspective representations of an assembly of roof-coveringelements according to the present invention with the correspondingtubing arrangement; FIG. 4 a shows the tubing arrangement being attachedto the roof-covering elements; FIG. 4 b shows the tubing arrangementbeing separated from the roof-covering elements;

FIG. 5 is a view from below of an assembly of roof-covering elementsaccording to the present invention with the corresponding tubingarrangement;

FIG. 6 are sectional representations of the assembly of roof-coveringdevices according to the present invention of FIG. 5; FIG. 6 a is thesectional representation taken along the line B-B of FIG. 5; FIG. 6 b isthe sectional representation taken along the line A-A of FIG. 5.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

FIG. 1 illustrates a conventional roof-covering element 10, generallyreferred to as a tile. In FIG. 1, the reference numeral 11 refers to anupper surface of the roof-covering element 10. The upper surface of theroof-covering element 10 can have different forms and profiles, and canalso present different patterns, colours or structures. The uppersurface 11 of the roof-covering element 10 can in particular be treatedby mechanical or chemical means in order to achieve a particularoptical, mechanical or thermic effect. The upper surface 11 of theroof-covering element 10 can also have a particular glaze or similarcoating. In addition, the roof-covering element 10 in FIG. 1 possessesan interlocking arrangement 13, 14, 15, which is used forinterconnecting adjacent roof-covering elements 10 when they are used inroof covering.

This interlocking arrangement 13, 14, 15 is basically built-up of bothhorizontal and vertical beads 13, 14 and grooves 15 in the peripheriesof the roof-covering element 10 which work together to interconnectsafely neighbouring elements 10 into a continuous assembly. It is wellunderstood that the interlocking arrangement 13, 14, 15 can compriseadditional interlocking, fastening and/or binding means (such as clampsor nails) for a safe and stable interconnecting, fastening and bindingof neighbouring elements 10 on the roof.

An assembly of conventional roof-covering elements 10 of FIG. 1, whichare juxtaposed in rows and columns and interconnected by means of theinterlocking arrangement 13, 14, 15 for covering one part of the roof isshown in FIG. 2. The reference numeral 20 in FIG. 2 refers to frameworkbars which function as support for the roof-covering elements 10.Typically, the framework bars 20 are made of wood. However, theframework bars 20 could also be made of any other suitable material. Theroof-covering elements 10 are hung from the framework bars 20 in anumber of parallel rows, whereby each row overlaps the row below it toexclude rainwater. As mentioned above, additional fastening means couldbe used in order to safely fasten the roof-covering elements 10 to theroof. The particular arrangement of the roof-covering elements 10therefore also allows to hide the fastening means (i.e. nails or hooks)that sustain the row situated immediately below. As a matter of course,different other ways of covering roofs using the roof-covering elements10 are imaginable, particularly with respect to the way in which theroof-covering elements 10 are arranged and/or interconnected.

Examples of the roof-covering element 10 according to differentembodiments of the present invention are shown in FIG. 3: FIG. 3 aillustrates a sectional representation of the roof-covering element 10according to a first embodiment of the present invention, and FIG. 3 billustrates a sectional representation of the roof-covering element 10according to a second embodiment of the present invention. In FIG. 3 a,the reference numeral 11 refers again to an upper surface of theroof-covering element 10 and the reference numeral 12 to a lower surfaceof the roof-covering element 10. As it can be seen in FIG. 3 a, theupper surface 11 of the roof-covering element 10 can have a particularshape or profile, which can be chosen based on aesthetic, functional,architectural or any other criteria. Although the upper surface 11 ofthe roof-covering element 10 in FIG. 3 a has a concave profile, theprofile or shape of the upper surface 11 of the roof-covering element 10can have any other form, including a convex or flat profiles. The lowersurface 12 of the roof-covering element 10 is basically flat, althoughother shapes of the lower surface 12 are possible. Nevertheless, as thelower surface of the roof-covering element 10 is basically not exposedto views, its shape can be chosen in any way, as soon as it does notlimit the functionalities of the roof-covering element 10.

The roof-covering element 10 of the first embodiment of the presentinvention in FIG. 3 a also comprises the interlocking arrangement 13,14, 15, consisting of beads 13, 14 and grooves 15. The beads 13, 14 andgrooves 15 of the interlocking arrangement 13, 14, 15 are designed insuch a manner that they are able of easily interconnecting neighbouringroof-covering elements 10. In particular, the bead 14 is designed towork together with the groove 15, while the bead 13 is designed to worktogether with the groove on the lower face of the bead 14. Moreover, theroof-covering element 10 comprises typically other beads and groovesextending in a direction perpendicular to the section plane in FIG. 3 a.It is however obvious, that the roof-covering element 10 can be providedwith other means allowing an easy and reliably interconnection ofadjacent elements 10. In this manner, any roof can be covered withcontinuous rows and columns or any other assembly consisting ofindividual roof-covering elements 10. The roof-covering element 10 ofthe first embodiment of the present invention in FIG. 3 a comprises arecess 14 a in the bead 14. The recess 14 a can in particular be usedfor deploying a fastening or binding means which can be used for abetter hold between two roof-covering elements 10. In this manner, theinterconnection between two elements 10 can be strengthened in order toachieve a particularly secure and resistant roofs, even under very badweather conditions. Of course, fastening or binding means forreinforcing this interconnection can also be placed at a different placeon the roof-covering element 10. On the other hand, the recess 14 a canbe used to adjust correspondingly the weight of the roof-coveringelement 10, when necessary.

The upper surface 11 and the lower surface 12 of the roof-coveringelement 10, as well as the interlocking arrangement 13, 14, 15 and otherparts of the roof-covering element 10 can be made of a same material.One or various parts can however be made of a material which isdifferent than the material of the other parts. In particular, at leastthe upper surface 11 of the roof-covering element 10 can at leastpartially be made of a metal alloy. This metal alloy can in particularcomprise a combination of copper (Cu), zinc (Zn), manganese (Mn) andiron (Fe). However, this metal alloy can also comprise any othercombination of these or other metals. This metal alloy can also containnon-metal substances, which are particularly necessary or advantageousfor achieving special properties of the alloy. At the same time, theother parts of the roof-covering element 10 can be made of anothermaterial, in particular of another metal or metal alloy, but also ofnon-metal materials such as clay, ceramic, glass, plastics or othersynthetic materials. For example, the upper surface 11 of theroof-covering element 10 can be made of a first metal alloy, the lowersurface 12 of the roof-covering element 10 of a second metal alloy, andthe interlocking arrangement 13, 14, 15 of a third metal alloy. It canbe appreciated that any other combination of materials is possible,without leaving the general inventive concept of the present invention.

The reference numeral 16 in FIG. 3 a refers to a cavity, formed insidethe roof-covering element 10, between the upper surface 11 and the lowersurface 12. The size, shape and dimensions of the cavity 16 can varywithout changing the fundamental idea of the present invention. Inparticular, this cavity 16 can extend over the whole area of theroof-covering element 10, but also comprise just a small area comparedwith the overall area of the roof-covering element 10. The cavity 16 isformed in such a way that a fluid can circulate inside the cavity 16.The fluid can in particular be water or a particular aqueous solution,but can basically be any other suitable fluid. The used fluid can inparticular also be an water/antifreeze solution, which can be used in avery important temperature range without any difficulties caused by lowtemperatures. In particular suitable antifreezes are propylene glycol,denatured alcohol and/or methanol). As fluid is confined in the cavity16 inside the roof-covering element 10 between the upper surface 11 andthe lower surface 12, the heat exchange between the fluid and theenvironment can easily be realised. In particular, the upper surface 11of the roof-covering element 10 stands in an continuous contact with theoutside air, such that the temperature difference between these twomedia can lead to the heating or cooling of the fluid inside theroof-covering element 10 without any additional action or mechanism.Moreover, metal alloys in general and particularly alloys containingcopper have very advantageous thermal characteristics, such that theheat exchange with the environment can be realised in an optimal way. Inaddition, being exposed to the sun, the upper surface 11 of theroof-covering element 10 is particularly subject to a very importantheating up, in the way that the fluid inside the cavity 16 of theroof-covering element 10 can easily achieve very high temperatures.

Furthermore, the roof-covering element 10 according to the firstembodiment of the present invention in FIG. 3 a comprises a nipple 17,which on it's own comprises an opening 17 a. The nipple 17 in FIG. 3 ais formed in the lower surface 12 of the roof-covering element 10. It ishowever evident that the nipple 17 can be formed in any other place onthe roof-covering element 10, including in particular the upper surface11, the interlocking arrangement 13, 14, 15, or side surfaces of theroof-covering element 10. Of course, the roof-covering element 10 cancomprise more than one nipple 17, if required. The opening 17 a of thenipple 17 is connected with the cavity 16 in such a way that the fluidcan enter and/or leave the cavity 16 through the opening 17 a of thenipple 17. The roof-covering element 10 can i.e. comprise a tap forclosing the opening 17 a of the nipple 17, once the fluid has beenfilled in or evacuated from the cavity 16. In this way, the cavity 16 ofthe roof-covering element 10 can be filled with the fluid for heatexchange with the environment and emptied after the fluid has reachedthe desired temperature.

A second embodiment of the roof-covering element 10 according to thepresent invention is illustrated in FIG. 3 b. The second embodiment ofthe roof-covering element 10 according to the second embodiment of thepresent invention has a very similar structure as the roof-coveringelement 10 according to the first embodiment of the present invention.The same reference numerals are again used to refer to the samecomponents: the reference numeral 11 refers to the upper surface and thereference numeral 12 to the lower surface of the roof-covering element10. The reference numerals 13, 14, 15 refer to the interlockingarrangement, and the reference numeral 16 to the cavity between theupper surface 11 and the lower surface 12 of the roof-covering element10. The reference numeral 17 refers to a first nipple with the opening17 a and the reference numeral 17′ to a second nipple which hasbasically the same structure and function as the first nipple 17. Thecavity 16 in this second embodiment of the present invention comprises achannelling system 18. The channelling system 18 comprises variousfurrows and twists which increase significantly the inner surface of thecavity 16. In such a way, the heat exchange between the fluid confinedinside the cavity 16 and the environment can be particularly effective.As the walls of the channelling system 18 are directly connected withthe upper surface 11 of the roof-covering element 10, the heat exchangebetween the upper surface 11 and the fluid inside the cavity 16 can alsobe realised in a very effective and easy way.

As it can be very much appreciated from FIG. 3 a and FIG. 3 b, thevisual aspect of the roof-covering element 10 according to these twoembodiments of the present invention do not differ whatsoever from theoptical appearance of a conventional roof-covering element. Their shape,including the shape and function of the interlocking arrangement 13, 14,15 of the roof-covering elements 10 are designed to reproduce in anexact manner the corresponding elements of a conventional roof-coveringelements. Moreover, the use of a particular alloy (i.e. the copper alloyCuZn₄₀Mn₂Fe₁ with its particular properties) allows the roof-coveringelement 10 according to an embodiment of the present invention to havesignificantly the same colour as conventional clay-made roof-coveringelements but without the need for any additional mechanical or chemicaltreatment of the surface. Moreover, the roof-covering element 10 of thepresent invention can preferably be designed in such a way to exhibitalso exactly the same weight as a conventional roof-covering elementhaving the same shape. This particular feature allows an easy exchangeof existing roof-covering elements and their replacement with theroof-covering elements according to the present invention without needfor any additional changes on the roofing structure or other roofelements. On the other hand, the roof-covering element 10 according tothese embodiments of the present invention does present the particularadvantage of heat exchange, without the above-mentioned disadvantages ofthe conventional solutions.

FIG. 4 shows an assembly of roof-covering elements 10 according to anyone of the embodiments of the present invention on a portion of a roofwith the corresponding tubing arrangement 25. FIG. 4 a shows theassembly with the tubing arrangement 25 being attached to theroof-covering elements 10 and FIG. 4 b shows the same assembly with thetubing arrangement separated from the roof-covering elements 10 . As itcan be seen, the individual tubes interconnect two elements 10. It isevident for any person skilled in the art that the arrangement of tubesand the choice of interconnection patterns can be varied withoutdeparting from the general inventive concept. The tubes are attached tothe nipples 17, 17′ of the corresponding roof-covering elements 10 andthus interconnect the cavities 16 of the elements 10. In this particularmanner, all individual roof-covering elements 10 build a linked systemin which the fluid can freely circulate throughout the system. In thissystem, it is in particular possible to create a fluid flow in adirection, where the fluid enters the system at a first roof-coveringelement 10 and leaves the system after having visited all roof-coveringelements 10 in the assembly. This flow can in particular be supported bymeans of a pump (not shown) or any other similar device. In this way, anoptimal heat exchange can be realised.

FIG. 5 is a view from below of an assembly of roof-covering elements 10according to the present invention with the corresponding tubingarrangement 25. FIG. 6 shows sectional representations of the assemblyof roof-covering devices 10 according to the present invention, shown inFIG. 5. FIG. 6 a is the sectional representation taken along the lineB-B of FIG. 5, while FIG. 6 b is the sectional representation takenalong the line A-A of FIG. 5. These Figures show one of the possiblestructures of an assembly of roof-covering elements 10 according to anyone of the embodiments of the present invention. The same referencenumerals are again used to refer to the same components, the structureand function of which, for simplicity, will not be exposed again.

Although the present disclosure has been described with reference toparticular means, materials and embodiments, one skilled in the art caneasily ascertain from the foregoing description the essentialcharacteristics of the present disclosure, while various changes andmodifications may be made to adapt the various uses and characteristicswithout departing from the spirit and scope of the present invention asset forth in the following claims.

1. A roof-covering element (10), having an upper surface (11) and alower surface (12), whereby for roof covering a plurality of elements(10) is juxtaposed in a particular way such that neighbouring elements(10) are interconnected by means of an interlocking arrangement (13, 14,15), and whereby the roof-covering element (10) comprises means forexchanging heat with the environment, characterised in that at least oneof the surfaces (11, 12) of the element (10) is at least partially madeof a metal alloy.
 2. The element (10) according to claim 1,characterised in that the metal alloy comprises any combination ofcopper (Cu), zinc (Zn), manganese (Mn) and iron (Fe).
 3. The element(10) according to claim 1 or 2, characterised in that the metal alloycomprises CuZn₄₀Mn₂Fe₁.
 4. The element (10) according to any one of theclaims 1 to 3, characterised in that a cavity (16) is provided insidethe element (10), between the upper surface (11) and the lower surface(12) of the element (10), whereby a fluid is circulable in the cavity(16) for heat exchange with the environment.
 5. The element (10)according to any one of the claims 1 to 4, characterised in that atleast one nipple (17) with an opening (17 a) is provided in at least onesurface (11, 12) of the element (10), whereby the opening (17 a) of thenipple (17) is connected with the cavity (16).
 6. The element (10)according to claim 4 or 5, characterised in that the cavity (16)comprises a channelling system (18).
 7. The element (10) according toany one of the claims 1 to 6, characterised in that the upper surface(11) and/or the lower surface (12) of the element (10) comprises a finstructure.
 8. The element (10) according to any one of the claims 4 to7, characterised in that the fluid is water and/or an aqueous solution.9. An assembly of roof-covering elements (10), comprising at least oneroof-covering element (10) according to any one of the claims 1 to 7,characterised in that a tubing arrangement (25) is provided forinterconnecting at least two roof-covering elements (10), whereby thefluid is circulable between the roof-covering elements (10) through thetubing arrangement (25).
 10. The assembly according to claim 9,characterised in that a pump is provided for circulating the fluidbetween the roof-covering elements (10).
 11. A heat exchange system in abuilding or a similar structure, using a fluid for heat exchange withthe environment, comprising a storage device for storing the fluid, apump for circulating the fluid in the system and a control device forregulating the heat exchange, characterised in that the heat exchangesystem comprises at least one roof-covering element (10) according toany one of the claims 1 to
 8. 12. A method of manufacture of aroof-covering element (10) according to any one of the claims 1 to 8.13. A method for roof covering using roof-covering elements (10)according to any one of the claims 1 to 8.